Along with " D . felix " ( sometimes misspelled " D . felise " ), a second species of " Diplosaurus " was constructed in 1877 by Marsh after he recombined " Hyposaurus vebbii ", named by Edward Drinker Cope in 1874, with " Diplosaurus " into a new combination, " Diplosaurus vebbii " . " D . nanus " was named by Marsh in 1895 but is now considered to be a nomen dubium.
